Some homeowners get so excited about remodeling jobs that they don’t think through the process.

Focused on the end result, they jump into the project and make major mistakes like choosing a contractor simply because he's the cheapest, hiring someone who doesn’t specialize in the work they’re having done or trying to oversee the job themselves to save money.

Other homeowners let fear stop them from undertaking the projects that would make their homes more beautiful, more comfortable and more enjoyable places to live.

They wonder whether all of the money they're spending will really increase the value of their home, even if the job goes well.

Regardless of which category you fall into, our expert tips will help you avoid the biggest remodeling mistakes. We want you to proceed with confidence and get a result you love.

Building codes vary by locality, and while most routine maintenance items don’t require permits, remodeling changes often do.

You might not know that you need permits for jobs like adding a bedroom, replacing a window or modifying plumbing, or that while your friend in the next town was able to redo her driveway without a permit, your town requires one.

Proceeding without the right permits could result in fines, delays, problems selling your house or even having to redo your project.

To get those permits — and many jobs require several — you’ll have to meet your city’s requirements for safe design and construction.

Even a small bathroom remodel requires permits in San Francisco, where interior designer Katie Anderson is based, and these can’t be obtained without construction drawings, she says.

Unless you are working with a design-build firm, you will need a designer or architect to create those drawings, because many contractors do not draft plans.

Doing the work yourself? DIY jobs require permits, too.

Exceptions include small jobs like replacing flooring or installing a new toilet in the same place.

Remodeling always costs more than you initially expect, especially if you’re not familiar with all the things that might go wrong.

Consulting with a professional before starting work will help you plan for contingencies and account for unexpected items like rewiring a kitchen that’s not up to code.

Older homes and larger jobs are more likely to have hidden expenses, as are projects involving plumbing, electrical or other work that is hidden behind walls and ceilings. There could be mold, leaks, corroded pipes, termite damage, fire hazards or asbestos.

Even the best contractor can't always identify these potential problems before work begins, so don’t assume the contract’s cost is what you’re going to pay.

Expect to spend 10% to 15% beyond that amount. If you can’t afford the higher, more realistic price, scale back the work, downgrade the materials or keep saving.

Any changes to the job once it’s underway should be added to your written contract and d in the same detail as the original work. Never give a contractor free reign over your budget.

Don’t expect your home’s value to increase by the amount you spend on the project, and you won’t be disappointed.

Remodeling projects never pay for themselves, let alone make money when you sell your home, according to Remodeling Magazine. It says the average project recoups just two-thirds of its cost in the form of higher property values.

Even those improvements with the highest returns — replacing the front door and exterior siding, or adding a wooden deck — won't cover their costs when the home is sold.

Just remember that you'll get the biggest bang for your buck by keeping your project in line with what’s standard for your neighborhood. Resist the temptation to overimprove.

If selling is your main concern, fix any maintenance problems before you remodel. Buyers don’t want to spend money replacing missing shingles or repairing leaky faucets. If your home is seriously outdated, modernization projects might help it sell faster, even if you don’t recoup all of your expenses.

If you’re not moving, the real return on your investment will be an emotional one. Improving your house should make it a more functional and enjoyable place to live, a place you’re happy to wake up in each morning and come home to at night.

It’s tempting to act as your own construction manager and general contractor on a remodeling project and to choose individual contractors for each trade.

But while you could save 10% of the project cost up front, the work might be poorly coordinated, take longer and have cost overruns, says John Salat, a licensed architect in Orange County, California.

You also have to factor in the cost of your own time and energy.

A better strategy is to first hire an architect, then hire a general contractor who subcontracts work out to specialists. Subcontractors have a greater incentive to do their best work under a general contractor because it means getting repeat business, Salat says.

The architect’s designs will incur an extra cost up front, but they will help you get competing bids from different contractors who will each base their estimates on the same scope of work.

That makes it easier to compare bids and potentially lowers construction costs and the overall project cost.

The architect can also serve as an extra pair of expert eyes to notice issues that may arise during construction.

If you want your remodeling project to look polished and professional, you need a designer as well as an architect and general contractor.

'Contractors are not designers,' says Katie Anderson, an interior designer in San Francisco. You need a good design to get an aesthetically pleasing and lasting solution to a problem.

The training and skill set for these two professions is quite different, Anderson explains. A designer has a more artistic eye, will explore the use of unusual materials, and will create a more unique and interesting result with colors and scale that are perfectly balanced and that complement the home’s architectural style.

While contractors are great technicians, Anderson says, they are more likely to think of how easily they can build or install something using familiar materials and processes, instead of thinking about the most attractive options. Contractors usually don’t have design training.

'A designer can see potential issues with the design a homeowner comes up with and can offer better solutions because of their design education and working experience,' she says.

Any contractor you hire should be licensed and in good standing. You don’t want them doing a shoddy job that looks bad and can make your home dangerous.

Contractors should have worker’s compensation and liability insurance. Without insurance, an injured worker might sue you since they can’t rely on their employer for help with medical bills and lost wages.

Contractors should also have a surety bond, which guarantees they will follow the law and gives you financial recourse if they don’t.

You can check a contractor’s license, insurance and bonding through your state contractors’ licensing board; call or check the website. The board can also tell you if anyone has filed a complaint about or claim against the contractor.

Ask the contractor for references. Call those clients to ask how responsive the contractor was, whether he stuck to the schedule and budget and how he handled any problems.

Also check Angie’s List, Yelp and the Better Business Bureau for both positive reviews and complaints. Look for trends in what customers report rather than focusing on any one story.

Even after vetting potential contractors, homeowners still make mistakes.

They choose generalists instead of specialists and end up with a lesser quality of work.

They don’t check licenses carefully enough and end up with a licensed carpenter doing their electrical work.

They might even let a contractor convince them to write a large check up front. After all, he has to buy materials, and he’s going to set aside days if not weeks for your project. If you cancel, he’ll have no work and no income.

Check with your state’s contractors licensing board for rules about the maximum deposit a contractor can ask for. It might be 10% or $1,000.

“The most costly project is one that needs to be done twice because it wasn’t done right the first time,” says Barry Miller, president of Simply Baths and Showcase Kitchens, a design-build remodeling company in Monroe, Connecticut.

His company recently took over a job where the previous contractor took $6,000 from the client, did two days of work, then disappeared. The homeowner’s house has been torn apart for months.

It’s understandable that you’d want to choose the contractor who gives you the lowest bid. With your plans and design already finished, aren’t you just hiring labor?

'Homeowners look at price as the primary differentiator and tend to assume that everyone will provide the same quality, level of service, turnaround time and the same set of specifications,' says Barry Miller, president of Simply Baths and Showcase Kitchens, a design-build remodeling company in Monroe, Connecticut.

But you can't know if you're comparing bids for a similar scope of work unless you give a detailed list of project specifications to each prospective contractor.

Your specifications should include the following:

Project summary.

Architect’s plans.

Designer’s plans.

Start and finish dates.

Details for each trade. For example, a paint job should specify the paint grade, number of coats and color, Miller says.

Special parameters. Miller says it’s important to let contractors know about factors that might complicate the job, such as a family member with asthma or your homeowner’s association’s limits on work hours and days.

After choosing a contractor, it’s time to turn your specifications into a detailed, written contract that you and your contractor will sign.

This agreement should thoroughly the scope of work, the materials to be used, cleanup and debris removal, the total price and the payment schedule.

You should also develop a plan for the order in which the work will be done, especially on larger jobs, says Charlotte, North Carolina-based designer DeAnna Radaj, owner of Bante Design.

For example, you wouldn’t want to paint before having electrical work done, which might require opening up walls, and you wouldn’t want to put in new flooring before you paint, because paint could drip onto your new carpet or hardwood floors.

Deciding what order you will do the work in also helps you do major projects in chunks as your budget allows, Radaj says.

Make sure to update the contract anytime your plan changes.

It’s also important to conduct walk-throughs with your contractor on a daily basis, Radaj says, to make sure the work is on schedule and going as planned.